JJD0E225
JJD series coin-type supercapacitor with 0.22F 5.5V for compact backup power applications.
Product Overview
Description
The JJD0E225 is a compact coin-type electric double-layer capacitor (EDLC) from Nichicon's JJD series, designed for space-constrained backup power applications. With 0.22F capacitance and 5.5V voltage rating (two cells in series), this supercapacitor is ideal for RTC backup and memory retention.
Featuring Nichicon's activated carbon electrode technology in a hermetically sealed coin package, the JJD0E225 delivers maintenance-free backup power with extremely low leakage current (<1μA). The coin form factor (11.5mm diameter × 5.5mm height) is compatible with standard battery holders.
This supercapacitor is rated for 1000 hours at 70°C and features an operating temperature range of -25°C to +70°C. The JJD series is ideal for applications requiring compact backup power without battery replacement, such as RTC backup, memory retention, and small sensor systems.
Product Series
JJD
Primary Application
Real-time clock (RTC) backup
Key Features
- Compact coin-type package (11.5mm × 5.5mm)
- 5.5V rating (two 2.7V cells in series)
- Ultra-low leakage current (<1μA)
- Maintenance-free operation
- 500,000+ charge/discharge cycles
- Hermetically sealed construction
- Compatible with standard battery holders
Specifications
| Capacitance | 0.22F ±20% |
|---|---|
| Voltage Rating | 5.5V DC |
| Temperature Range | -25°C to +70°C |
| Ripple Current | 0.1A |
| ESR | 25Ω @ 1kHz |
| Lifetime | 1000 hours @ 70°C |
| Termination | Coin Type |
| Package | 11.5mm × 5.5mm |
| Qualification | Industrial Grade |
| Specifications | Coin Type, Low Leakage |
Applications
Real-time clock (RTC) backup
Electronic system design
SRAM memory retention
Electronic system design
Small sensor backup power
Sensor signal conditioning
Handheld device backup
Electronic system design
Medical device backup
Medical electronics
Security system backup
Electronic system design
FAE Expert Insights
"The JJD0E225 is my standard recommendation for replacing coin cell batteries in RTC and memory backup applications. The coin form factor makes it a drop-in replacement for CR1220 or similar batteries, eliminating the need for PCB redesign. The ultra-low leakage current (<1μA) is critical for long backup times - I've calculated that this supercapacitor can maintain an RTC for 30+ days on a single charge. The 500,000+ cycle life means it will outlast the product itself, eliminating battery replacement costs and environmental disposal issues. I particularly like that it uses standard battery holders, making assembly simple. For applications requiring longer backup, I recommend the larger JJD0E105 (1F) or JJC series."
Perfect battery replacement for RTC and memory backup applications
— Jennifer Liu, Senior FAE, BeiLuo
Frequently Asked Questions
How long will the JJD0E225 maintain an RTC during power loss?
RTC backup time depends on RTC current consumption and allowable voltage drop. Calculation: t = C × (V_initial - V_final) / I_rtc. Typical RTC draws 0.5-2μA and operates down to 1.8-2.0V. Example: JJD0E225 (0.22F) at 5.5V, RTC draws 1μA, minimum voltage 2.0V: t = 0.22 × (5.5 - 2.0) / 0.000001 = 0.22 × 3.5 / 0.000001 = 770,000 seconds = 8.9 days. For lower current RTC (0.5μA): t = 0.22 × 3.5 / 0.0000005 = 1,540,000 seconds = 17.8 days. For higher current RTC (2μA): t = 0.22 × 3.5 / 0.000002 = 385,000 seconds = 4.5 days. Include supercapacitor self-discharge (~1-5μA) in calculations. For longer backup, use JJD0E105 (1F) which provides 4-5x longer backup time.
Calculate based on your specific RTC current consumption or contact FAE for RTC selection guidance.
Can I use the JJD0E225 as a direct replacement for coin cell batteries?
Yes, JJD0E225 is designed as a drop-in replacement for coin cell batteries like CR1220, with important considerations: Physical compatibility: 11.5mm diameter × 5.5mm height fits standard CR1220 battery holders. Voltage differences: CR1220 provides 3.0V nominal, JJD0E225 provides 5.5V (charged) down to 0V (discharged). For 3V circuits, use a voltage regulator or select JJD series with appropriate voltage. Charging: Unlike batteries, supercapacitors must be charged before first use. Implement a charging circuit (current-limited to <100mA) or ensure your system provides charging current. Backup time: Calculate based on load current - supercapacitors provide shorter backup than batteries but unlimited cycles. Cost: Higher initial cost than batteries, but eliminates replacement labor and disposal costs over product lifetime. Environmental: No hazardous materials, RoHS compliant, no special disposal required.
Verify voltage compatibility with your circuit or implement voltage regulation for 3V systems.